Many electronic devices include components that include semiconductors; for example, components that have a semiconductor layer in contact with a dielectric layer. For example, a semiconductor layer and a dielectric layer commonly termed a “gate dielectric” may be part of a Thin Film Transistor (TFT).
Both the physical and chemical nature of the gate dielectric is thought to influence the electronic performance of the organic semiconductor at the interface with the gate dielectric. This interface is critical to performance as charge is transported from source electrode to drain electrode through the organic semiconductor along this interface when the organic TFT (OTFT) is in the ON state, that is when a certain gate to source voltage bias has been reached or exceeded and the drain current has risen exponentially. Thus, gate dielectrics are sought that enable superior electronic performance, such as high charge carrier mobility, high ON/OFF current ratio, low OFF current, and small sub-threshold slope in combination with organic semiconductors.
One area of improvement needed for the implementation of OTFTs in commercial products is more consistent or repeatable electronic performance between OTFTs fabricated in an identical manner, and more consistent or repeatable performance of the same OTFT from cycle to cycle. Less hysteresis in the OTFTs during their operation is sought. Hysteresis may result during driving of the OTFTs due to various factors including charges being trapped and accumulated between the organic semiconductor and the gate dielectric, or temporary polarization of the gate dielectric, or moisture being absorbed by the gate dielectric.